An air conditioner implying a cooler, a heater or both of them is classified into a window type and a split type. In the case of the cooler, a split type air conditioner includes an indoor unit installed indoors for cooling a room, and an outdoor unit connected to the indoor unit through refrigerant pipe lines and installed outdoors to contact air, for performing condensation heat exchange on a refrigerant gas in a condenser by using external air as a cooling medium, and supplying the condensed refrigerants to an evaporator of the indoor unit through the refrigerant pipe lines. The indoor unit is composed of the evaporator for performing cooling heat exchange for evaporating the refrigerants and absorbing evaporation heat from internal air, and a ventilating fan for circulating internal air, and the outdoor unit is composed of a compressor for compressing the refrigerant gas and supplying the compressed gas to the condenser, the air-cooled condenser for condensing the refrigerant gas from the compressor, and a cooling fan for forcibly ventilating external air to the air-cooled condenser to cool and condense the refrigerant gas. The compressor, the air-cooled condenser and the cooling fan of the outdoor unit are installed in an outdoor unit casing composing the outer appearance. The conventional hexahedral outdoor unit casing has an air suction unit for sucking air to the air-cooled condenser at its three sides, and an air discharge unit for externally discharging air absorbing condensation heat from the refrigerant gas by the heat exchange in the air-cooled condenser on its top surface.
However, the conventional outdoor unit for the air conditioner is restricted in installation spaces due to high density and strict environment regulations of cities, and increases civil applications due to noise and heat. Especially, a common residential area such as large-scaled apartment buildings regulates the outdoor units to be installed in indoor verandas to improve the appearance and prevent noise.
In order to solve the foregoing problems, Japanese Laid-Open Patent Publication 6-101873 suggests an air conditioner mounted building where an indoor unit of an air conditioner is installed indoors or adjacent to a room intended to be air-conditioned, and an outdoor unit of the air conditioner is installed outdoors, wherein an opening is formed on the outer wall or roof, a louver is installed in the opening, the outdoor unit of the air conditioner is positioned in the louver, and suction/discharge of the indoor unit is performed through a gap between louver plates.
In addition, Japanese Laid-Open Patent Publication 3-213928 discloses a wall built-in type outdoor unit for an air conditioner including an outdoor unit main body for the air conditioner which is built in the wall and which includes a frame having the same size and thickness as the wall, a suction hole for heat exchange air installed on the same surface as the outdoor unit main body, and a discharge hole for heat exchanged air.
FIG. 1 is a cross-sectional view illustrating a conventional louver unit. Referring to FIG. 1, the louver unit 1 is divided into a suction area 7a and a discharge area 7b on a rectangular space inner wall formed on an outer wall 2 of a residential and/or commercial building, and a plurality of louver blades 8 which are externally protruded with the same length are installed in each area.
The suction area 7a of the louver unit 1 contacts with a suction unit 11a of the outdoor unit, and the discharge area 7b of the louver unit 1 contacts with a discharge unit 11b of the outdoor unit. That is, air is sucked through gaps between the louver blades 8 of the suction area 7a, supplied to the suction unit 11a of the outdoor unit, heat exchanged therein, discharged from the discharge unit 11b of the outdoor unit, and discharged through gaps between the louver blades 8 of the discharge area 7b of the louver unit 1.
However, an open/close operation of the louver blades 8 is interrupted due to external factors (rain, snow, ice, dust, etc.), and thus the louver blades 8 may not be normally operated after an extended period of time.
In addition, the louver blades which have not been used for a long term may have problems due to the external factors.
The conventional outdoor unit does not suggest an apparatus and method for confirming an open/close state of the louver unit 1. Therefore, when the louver unit 1 is not normally operated due to errors, external air is not smoothly sucked through the suction unit 11a of the outdoor unit, and discharged through the discharge unit 11b of the outdoor unit. As a result, cooling/heating performance of the outdoor unit is rapidly reduced, and thus refrigerants are not efficiently heat exchanged, which has detrimental effects on performance of the indoor unit.
Moreover, when an overload current is transmitted to a driving source for operating the louver blades, the louver blades are closed or a driving member is out of order due to the overload current, to interrupt the operation of the outdoor unit.
In addition, mis-operations of sensors or switches of the outdoor unit are not sensed. Accordingly, the outdoor unit may not be normally operated.
The louver unit of the outdoor unit maintains a constant open angle of the louver blades to open or close the louver blades. As illustrated in FIG. 1, the louver blades opened by about 45° can intercept rain drops in a rainy day (100% of humidity). However, when external humidity is low, for example in a sunny day, such an angle increases a fan resistance, to interrupt suction/discharge of air.